I'm sorry to hear that it was stressful. There is some discomfort to be expected as you begin to face things that you don't find welcoming.

I'm no expert on the subject, but having gone through something similar, have a few thoughts....

When I was doing anxiety work, and particularly going into spaces that would cause anxiety, there was a "mode" that I needed to get into, which was a mindset of acceptance. Let the thing come at you, observe it, and let it pass. Don't fight it, even though that might be your instinct. Did the therapist you are seeing give you any ideas or guidelines about that sort of thing?

If you're fighting the feelings and thoughts, you might end up making things worse- making yourself more anxious. I think it is important how you approach the exposure.

I did a quick search and found an article a doctor wrote about Dr. Weekes method. She talked a lot about "floating" through the anxiety when it comes up. The article might give you some ideas as to how to approach your exposure so it's not so traumatizing. And again, I highly, highly recommend checking out her book. One of the more critical parts of the book (for me) was that she explains how the nervous system works, and why you end up in the anxiety pattern. Just understanding that changed a lot about how I looked at anxiety and agoraphobia.

Claire Weekes: Float Through Anxiety